I want to talk about different types of difficulty. A lot of times, people will describe a game as difficult without really looking deeper, which feel misses a lot of potential for analysis. I want to break down the concept of difficulty into a few different sliding scales:
Skill Window: The raw difficulty of completing a challenge in the game. The amount of skill with which you must interact with the game’s mechanics. These skills could be reflexes, accuracy, strategy, perception, and so on.
Simple vs. Complex: The amount of mental processes the player has to keep track of while playing. The amount of considerations the player needs to make, and the distance they need to plan into the future.
Forgiving vs. Unforgiving: How many allowances the player is afforded.
Low Stakes vs. High Stakes: How much can you lose (in terms of progress and/or resources) when you fail.
Recoverability: Do you have a chance to recover from your mistakes? How hard is it to do so? How many opportunities do you have to do so?
Readability: How much information does the game provide you. When you do something wrong, do you know exactly what it was? Do you know how to fix it?
Short Term Consequences vs. Long Term Consequences: How long does the effect of failure last. Does the player simply go back a few minutes and try the challenge again, or does the failure continue to negatively affect the player hours later?
Positive Feedback Loop vs. Negative Feedback Loop: Is it hard to recover from failure, and easy to push success forward, or is it easy to recover from failure, but hard to maintain success.
Alright, with that out of the way, let’s look at some examples and see how they fit along these scales:
Difficult indie platformers such as VVVVVV and Super Meat Boy: These sorts of games focus mainly on high skill and few allowances. The levels require quite a bit of dexterity, as well as a good plan, to complete, and a single mistake means returning to the last checkpoint. Note, however, that these games have low stakes and very short term consequences: you usually go back to the beginning of the current challenge, and once you succeed at the challenge, there are no lasting effects from your previous failed attempts. Because of this, there are also no positive or negative feedback loops present, since success or failure don’t effect your future chances of success or failure. It doesn’t matter if it took you 1 or 100 tries to beat a level, the next level will start the same way, and you’ll be in the same condition. Complexity is also fairly low, in that you generally only have a couple modes of interaction with the world (run, jump, wall jump, ect…). The only real complexity comes in from how many obstacles there are to keep track of and plan around in the level.
Dark Souls: Dark Souls is interesting not only because it’s fairly famous (infamous?) for being difficult, but also because many people who have played the game extensively will, with a straight face, tell people that the game actually isn’t all that difficult, and I think that dichotomy is worth exploring. The main issue here is that the game is not as high-skill as it seems: the game moves fairly slowly and most of the time you have fairly large windows in which to act. However, the game is very unforgiving, and a mistake could cost you very highly depending on the circumstances. If you miss an attack, the long attack animations leave you open for enemy attacks, which can then stun you and leave you open for more enemy attacks (Note that this would be a short-term Positive Feedback Loop). However, if you survive an encounter, you have a limited resource in the form of Estus which you can use to recover.
Because of the long space between checkpoints, the stakes get higher and higher until you reach the next bonfire. There are also a lot of situations where player mistakes are somewhat opaque, and require the player to try various things until they find one that works. For example, when I first started playing Dark Souls, I had trouble with the Parry. You have a fairly small window to parry, and if you fail, it’s hard to tell if you parried too soon or too late. (The game got a fair amount easier when I stopped even trying to parry). The game is fairly complex as you have to keep track of your surroundings, maneuver to get the best position, be aware of how long various actions take, and be careful not to make mistakes. It’s also worth noting that there are positive feedback loops that extend for longer than just one encounter, in the form of Souls and Humanity. You get these resources by battling enemies, and you lose them by dying, then dying again before you can recover them from your corpse. If you die once, the stakes are raised to include the resources you had gathered, and if you are doing really poorly and die twice, you lose those resources, constituting a positive feedback loop. If, on the other hand, you are doing really well, you will continue to accumulate Souls and Humanity (which in turn increases the amount of items you find) which serves as the other side of the possitive feedback loop.
Megaman: Megaman is a fairly high-skill game. The encounters are fairly simple, but you need a good plan and precision to get through an encounter. You’ve got enough health that the game will forgive a few mistakes (unless you fall down a bottmless pit), however, because of the skill level, if you keep throwing yourself at an encounter that you haven’t figured out the trick for, you’ll quickly eat up your allowances. The game has limited lives: your stakes are either a small amount of progress and one life, or, if you’ve run out of lives, an entire level’s worth of progress. However, other than lost progress, there are no long-term consequences to failure. You can recover some health with items that enemies drop, but you don’t really have much control over it. The game is very readable. Everything is very up front about how it works, and encounters can be solved by observing enemy patterns and having good control over your own movement. There’s also an interesting game-wide positive feedback loop: each level you beat provides you with a weapon that will make further levels easier.
XCOM: For the sake of convenience, let’s focus specifically on the recent XCOM: Enemy Unknown, although much of this would also be true about X-COM: UFO Defense. The game takes quite a bit of skill (which, in this case, means tactical ability, since this is a turn based game). You have to be very careful in choosing moves. By the standards of a tactics game, Enemy Unknown comparatively simple. Your characters have a limited moveset, enemies act in fairly simple ways, and a lot of the game comes down to positioning and proper use of cover. However, the game is fairly unforgiving: your units don’t take many hits, and if one of them dies, it can set off a positive feedback loop through your units panicking that will wipe out your squad. The game also has long-term consequences. Units that die in battle are permanently dead and failed missions will reduce your support. Losing a mission doesn’t end the game, but they can lead you to ultimately losing the entire game (Of all the examples I’ve listed in this article, this is the only one where actually losing the game, rather than losing progress, is a possibility). On the other hand, success will raise your units’ levels. As far as recoverability: on the small scale, you can heal wounded units and revive unconscious units with a med kit. On the larger scale, it is very hard, and often impossible, to recover from a failed mission or a mistake in development, and because of the nature of the game, the actual game-over could come a while after you’ve sealed your fate. The positive feedback loops in the tactical portion of the game can be rough, but the positive feedback loops at play in the overarching game are absolutely brutal.
The point of all of this is that difficulty is a very multifaceted element of game development. The idea of difficulty and challenge is so fundamental to game design, I think it’s important to fully analyze what makes a game difficult, and establish a vocabulary to describe the different ways in which a game can be difficult. This article is by no means comprehensive, I’m sure there are modes of difficulty that I’ve left out or haven’t thought of. But it should provide a starting point for discussing difficulty in more detail than “this game is hard/this game is easy.”.